Blockchain technology is applied in many industries and is steadily gaining support and users' trust. Many start-ups and businesses try to develop unique web platforms or mobile apps with a wide range of blockchain usage. As the blockchain and crypto markets thrive, developers have many opportunities and projects to develop, like trading bots, payment applications, or business settlement solutions. In this article, we'll figure out how API is used for blockchain and how API integration might benefit the app. 

What Is Blockchain API?

Application Programming Interface (API) integration is used to communicate with blockchain nodes or client networks. By doing so, it gets data and displays it to the user. APIs can be used for transactions, managing accounts, crypto trading, making analytics, and providing security. Top blockchain APIs are considered secure, easy to use, and reliable in the long run. Distributing data securely might be along with blockchain technology, but it's safer and more convenient. Choosing one is no easy feat, as the diversity of APIs is truly impressive.

Key Factors Before Choosing Blockchain API

Developers or development teams have preferences when it comes to choosing programming languages, architecture patterns, frameworks, or libraries. The same goes for top blockchain API integrations, but it's advisable to check for some things first.

• Technology used. For the developer, it's important to use open-source codes when choosing the technology of a blockchain API. Open-source code can be tested by others, and mistakes are eventually avoided.
• Compatibility. Ensure that the API that you choose has the functionality to support certain coins. It is considered mainly for cryptocurrencies apps, but still.
• Performance. The more transactions or processes you need to run at the same time, the more careful your choice should be. Some blockchain APIs perform a few transactions per second, and others run thousands. It's worth considering microservices when building an app with blockchain APIs as it allows for dealing with high loads and continues to be responsive and very fast in processing users' requests.

Blockchain has APIs for wallet services, payment processing, blockchain exploration, and text queries. They provide WebSocket as well as market data API.

Top Blockchain APIs by Categories

WebSockets and REST API for Blockchain

There are two types of blockchain protocols that let transmit data or exchange information. Let's find out how WebSockets work first. The WebSocket API is a technology that allows opening a two-way interactive communication session between the user's browser and a server. Essentially, it's a stateful protocol used to establish constant client-server communication. WebSocket API allows developers to receive real-time notifications about the newest transactions and blocks. It's faster and easier than the Representational State Transfer (REST) API, which is a traditional way of transmitting messages. Usually, both APIs might be established, but it depends on web application requirements.

For faster and highly efficient communication sessions, use WebSockets as they don't need the HTTP request/response overhead for every message sent and received. REST API for blockchain is better fitted for occasional communication in a typical GET request scenario to call RESTful APIs.

Payment Processing API

In order to connect a business's checkout function to the payment system, developers integrate a payment processing API. Payment API integrations are especially useful in cryptocurrency exchanges. After the subscription fee is paid, you can use the service with gateway functionality. Among the popular ones are CoinGate, ALFAcoins, SpicePay, Square, Stripe, and Helcim. Consider the following factors when choosing this API:

• Price (it depends on transaction volumes, card-present or card-not-present, etc.)
• Security (some are not suitable for high-risk operations.)
• Account stability (some payment APIs can undergo stability issues, so research before and look at reviews).

Wallet Services

Usually, they are combined with payment processing APIs and are used to store digital assets. The main application is purchasing, selling, sending, receiving, and storing digital assets. The most common blockchain API in this category is probably Coinbase, as it's easy to implement into an existing application. Other examples are CromaWallet API and Blockchain API. The last one allows developers to create wallets for loading and redeeming funds.

Blockchain Data API

We need blockchain data APIs to follow market trends and get real-time data about "top cryptocurrencies." Some developers prefer to create data APIs on their own, developing tools such as portfolio monitoring, statistics aggregation, and even trading bots. A lot of such services, though, are provided free of charge or with free trial periods, like Nomics, CoinAPI, CoinMarketCap, or Binance API. Integrating blockchain data API is essential for consulting the data on the operations and transactions within the blockchain in JSON format.

Simple Query API

To build decentralized apps, we need to query data on the blockchain. In simple words, Query API allows pulling data via requesting data displayed in your Branch dashboard without accessing the Dashboard itself. The simplest example of a blockchain explorer is Blockchain Info API, a plaintext-based API that retrieves data from Blockchain.info for free. The more resources you want to get data from, the pricier it gets. For instance, Daneel API has unlimited calls and collects and filters information from around 500 sources.

API Marketplaces

There is also a modern approach that offers a lot of third parties APIs in one place. It simplifies the search for developers but might have some issues with security. One example would be Rakuten RapidAPI, a platform with 8,000+ third-party APIs. There are others with similar options, so to choose one, you can check out APILayer, Celigo, Zapier, or Integrately. Most of them have a 14-day free trial.

Quick Sum Up

Blockchain APIs are vital while developing solutions for the quickly changing market. They are useful for supporting a cooperative environment, controlling the chain, and serving as a type of quality control in different industries. The top applications of blockchain APIs are in crypto exchanges and trading. Nevertheless, they significantly ease the work of developers. Also, the API documentation can be checked on the go and reviewed by others, which is essential for project security. Many needed APIs come for free and are easy to integrate into web applications, but researching and comparing a wide range of APIs shouldn't be overlooked.